Adjustable propeller



Dec. 27, 1932. BURSC'W ET AL 1,892,035

ADJUSTABLE PROPELLER Filed May 19, 1931 3 Sheets-Sheet l Invenlor;

u v Bygmw Dec. 27, 1932. BUIRSON ET AL 1,892,035

ADJUS TABLE PROPELLER Filed May 19. 1951 3 Sheets-Sheet 2 (warm? Nazism 3 4 Invenhms Thomas .Burson Charles W Jen/{0715 qllomey Patented Dec. 27, 1932 'rnomsmmson AND CHARLES w. JENKINS, or nnennv, 011110 ADJUSTABLE PROPELLER Application filed Kay 19,

The present invention relates to propellers such as aircraft propellers and the like, and particularly to the type having adjustable blades; and an important object of the invention is to provide an improved form of adjustable blade propeller wherein the'pitch of the blades thereof may be simultaneously changed so as to vary or reverse the aerody namic effect of the propeller during rotation of the propeller while the aircraft or the like is in flight.

The invention consists in novel means for effecting the adjustment of the' blades so constructed that the blades and associated structure may be easily disassembled for repair or replacement as hereinafter more fully described and claimed, and as shown in the drawings wherein:

- Figure l is a side elevation of the propeller embodying the features of our invention.

Figure 2 is an end elevation thereof.

Figure 3 is a sectional view taken substantially on the line 33 of Figure 2.

' Figure 4 is a section taken substantially on the line 4-4 of Figure 1.

Figure 5 is a sectional view through the slidable collar.

Figure 6 is a detail section through the inner end of one of the blade shanks.

Figure 7 .is a sectional view taken substantially on the line 7 7 of Figure 3.

Figure 8 is a plan view of the disks.

Figure 9 is a detail section taken substantially on the line 9-9 of Figure 3.

Referring to the drawings in detail it will be seen that the numeral 5 designates a transversely elongated sectional hub, the sections of which are held together by bolts 6.

Shanks 7 of blades 8 are journalled longitudinally in the hub 5 in axial alinement with each other and terminate at their inner end in a closed chamber9 formed in the center of the hub access towhich may be obtained by removal of inspection plate 10 which is held in place by screws 11 so as to cover an opening in what is referred to herein as the front section of the hub, which pening leads into, the closed chamber 9. he shanks 7 are formed with annular beveled shoulders 12 5 and 14 engaging roller bearings 15 and 16 1931. Serial No. 538,522.

respectively in the outward ends of the hub .and in the chamber 9 respectively. Disks 17 are mounted on the radially inward ends of the shanks by means of screws 18. p

The periphery of each of the disks 17 have indentations 19 to receive spring pressed pins 20 in sockets 21 carried by and projecting inwardly from the inspection plate 10. Lugs 22 project radially from the peripheries of the disks and engage in grooves 23 formed in the chamber 9 whereby rotation of the shanks of the blades is limited. A plate 25 with an oblong opening 23 therein is disposed between the disks 17 and has oppositely disposed notched radial extensions 27 for receiving eccentrically located pins 28 projecting inwardly from the opposed faces of the disks 17. "Rods 30 are slidable throu h the rear section of the hub into the cham er 9 where they are connected to the plate 25. Outward of the hub the rods 30 are engaged with a collar 29 slidable on the propeller shaft 30 fixed to the rear section of the hub. Numeral 31 designates a lever which may be located inside the aeroplane or the like and which is connected by a link 32 with a fork 33 engaged with the collar 29 which is grooved as at 34. for this purpose. Obviously by sliding the collar 29 by swinging the lever 31 the shanks 7 may be rotated on their axes and the pitch of the blades changed as may be desired so as to attain the aerodynamic efi'ect desired and efiicient operation under different flying conditions within predetermined limits.

It is thought that the construction, operation, utility and advantages of this invention will now be quite apparent to those skilled in this art without a more detailed description thereof.

The present embodiment of the invention has been described in considerable detail merely for the purposes of exemplification since in actual practice it attains the features of advantage enumerated as desirable in the statement of the invention and the above description.

It will be apparent that changes in the details of construction, and in the combination and arrangement of parts may be resorted to without departing from the spirit or scope of the invention as hereinafter claimed or sacrificing any of its advantages.

Having thus described our invention, what we claim as new is:

1. A reversible pitch aircraft propeller comprising a sectional hub comprising front and back sections which form a central interior closed chamber, and a pair of opposed radial openings in the hub leading into the chamber, a propeller blade having a shank rotatable fitting in each radial opening and extending into the chamber, an inspection plate covering an opening in the front section which leads into the chamber for placing lubricant therein, propeller shaft attaching g means on the rear section of the hub, a pro.- peller shaft attached to the rear section of the propeller; an eccentric lug projecting inwardly from the inward end of each shank, the inward ends of said shanks being spaced from each other, a transversely shiftable member located between the inward ends of the shanks and provided with opposed notches for receiving the lugs on the shanks,

means carried on the propeller shaft having members slidable through the rear section of the hub and connected to the shiftable member for moving the same on the axis of the propeller for rotating the propeller blades to change the pitch thereof while the propeller is rotating.

2. A reversible pitch aircraft propeller comprising a sectional hub comprising front and back sections which form a central interior closed chamber, and a pair of opposed radial openings in the hub leading into the chamber, a propeller blade having a shank rotatable fitting in each radial opening and extending into the chamber, an inspection plate covering an opening in the front section which leads into the chamberfor plac ng lubricant therein, propeller shaft attaching means on the rear section of the hub, a propeller shaft attached to the rear section of the propeller; an eccentric lug projecting inwardly from the inward end of each shank, the inward ends of said shanks being spaced fromeach other, a transversely shiftable the propeller; an eccentric lug projecting inwardly from the inward end of each shank, the inward ends of said shanks being spaced from each other, a transversely shiftable member located between the inward ends of the shanks and provided with opposed notches for receiving the lugs on the shanks, means carried on the propeller shaft having members slidable through the rear section of the hub and connected to the shiftable member for moving the same on the axis of the propeller for rotating the propeller blades to change the pitch thereof while the propeller is rotating, and spring urged detent means carried by the inspection plate for normally engaging in openings on the inward ends of the shanks for preventing unwanted rotation of the propeller blades relative to the hub, and radial projections on the inward ends of the shank engaged in grooves in the chamber for limiting the rotation of the shanks in either direction.

In testimony whereof we aflix our signatures.

' THOMAS BURSON.

CHARLES w. JENKINS.

member located between the inward ends of the shanks and provided with opposed notches for receiving the lugs on the shanks, means carriedoii the propeller shaft having members slidable through the rear section of the hub and connected to the shiftable member for moving the same on the axis of the propeller for rotating the propeller blades to change the pitch thereof while the propeller is rotating, and spring urged detent means carried by the inspection plate for normally engaging in openings on the inward ends of the shanks for preventing unwanted rotation of the propeller blades relative to the hub.

3. A reversible pitch aircraft propeller comprising a sectionalv hub comprising front 

